Syringe with upper and lower bores



1965 H. BLANKENSHIP, JR 3,216,616

SYRINGE WITH UPPER AND LOWER BORES Filed March 2. 1964 Q I i i gm Vx7007 e," .5/0/7A'e/7Jfi 0, d/z

INVENTOR.

BY fig 5 2 ATTUR/VEVJ United States Patent 3,216,616 SYRINGE WITH UPPERAND LOWER BORES Homer Blankenship, Jr., 3601 White Oak Drive, Houston,Tex. Filed Mar. 2, 1964, Ser. No. 348,588 7 Claims. (Cl. 222-47) Thisinvention relates to new and useful improvements in syringes.

An object of this invention is to provide a new and improved syringefrom which accurately measured quantities of fluid may be dispensed by aplunger displacing same in a syringe tube having a calibrated 'bore, andwherein such bore is formed without grinding to dimension, therebyreducing the manufacturing cost and facilitating interchangeability ofsyringe tubes and plungers.

Another object of this invention is to provide a new and improvedsyringe having a body with at least two different internal boredameters, and also having a plunger for each such bore.

A particular object of this invention is to provide a new and improvedsyringe wherein mixing and blending of two difierent fluids may beeffected within the syringe body in measured quantities.

A further object of this invention is to provide a new and improvedsyringe having a syringe body with two different internal diameterbores, each of which is calibrated, and also having plunger means fordrawing different measured quantities of fluids into such bores formixing and/or blending in desired proportions and for thereafterdischarging such mixed and/or blended fluids in measured quantity fromthe syringe.

Still another object of this invention is to provide a new and improvedsyringe having a body with a lower bore and an upper bore, wherein theupper bore is of a larger diameter than the lower bore, and wherein anouter plunger is slidable in the upper bore and an inner plunger isslid'able in the lower bore, such outer plunger sealing off the lowerbore at its upper end to enable the inner plunger to discharge ameasured quantity of fluid from the lower bore even though the innerplunger does not have a precision fit within the lower bore.

A specific object of this invention is to provide a new and improvedsyringe having a body made of glass or similar transparent material,with a two-part plunger therein, one part of which is made of plastic orother material capable of forming a seal in the bore of the body, andthe second part of which is formed of metal wire or similar material forserving as a plunger.

The preferred embodiment of this invention will be describedhereinafter, together with other features thereof, and additionalobjects will become evident from such description.

The invention will be more readily understood from a reading of thefollowing specification and by reference to the accompanying drawingsforming a part thereof, wherein an example of the invention is shown,and wherein:

FIG. 1 is an elevation of the syringe of this invention in the normalassembled condition; and

FIG. 2 is an exploded view, partly in elevation and partly in section,illustrating the principal components of the syringe of this inventionin a disassembled condition.

In the drawings, the letter S designates generally the syringe -of thisinvention which includes a tubular body 10 formed of glass or othersimilar material, preferably transparent. Such body 10 is provided withan upper bore 11 and a lower bore 12. An outer plunger is disposed formovement in the upper bore 11 for drawing fluid into the bores 11 and 12and for performing other functions, as will be An inner plunger 20 isadapted to be positioned within the bore or longitudinal opening of theouter plunger 15, and its lower portion serves to discharge fluid inpredetermined amounts from the lower bore 12 through a needle 25, aswill be more fully explained.

Considering the invention more in detail, the body 10 is preferablyprecision bore glass tubing in which the glass is shrunk over a mandrelto obtain the prescribed inner dimensions. As will be more evidenthereinafter, one of the advantages of the present invention resides inthe fact that the bores 10 and 12 do not have to be precision ground,thereby eliminating an expensive grinding operation heretoforeconsidered necessary in most types of syringes. By way of example, theinside diameter of the lower bore 12 may be 0.0206 inch plus or minus0.0002 inch. Such tolerances are obtained with the precision bore tubingwithout the necessity for grinding. The upper bore 11 may have, by wayof example, an inside diameter of 0.2500 inch plus or minus 0.0002 inch.Such dimensions can also be obtained with the precision bore tubing andwithout the necessity for grinding.

The upper bore 11 and the inner bore 12 are joined by an internaltapered or inclined wall surface 14 which serves as a seating or sealingsurface in conjunction with the outer plunger 15, as will be described.

For convenience in handling, a flange 10a is preferably provided on thebody at its upper end as illustrated. The needle 25 is secured to thelower end of the body 10, preferably by inserting same within a suitableenlarged opening 12a at the lower end of the inner bore 12'. An epoxyresin or other adhesive suitable for bonding the metallic needle 25 tothe glass body 10 is preferred for retaining the needle 25 in anattached position with'respect to the body 10. It is noted that theneedle 25 is shown with a reduced diameter point 25a, but it will beunderstood that various other types of needles may be employed,depending upon the particular us The needle 25 is of course hollowthroughout its length so as to admit fluid into the bores 12 and 11 andto also permit the discharge of fluid therefrom.

The outer plunger 15 is preferablymade of polytetrafiuoroethylene, soldunder the trademark Teflon, which material is especially suitable sinceit provides for substantially frictionless movement within the upperbore 11 while also maintaining effective seals as Will be more evidenthereinafter. In the usual case, with the bore 11 of the internaldiameter heretofore specified the external explained in detail.

diameter of the outer plunger 15 is 0.2497 inch.

The outer plunger 15 has an internal longitudinal passage or opening 16,which is reduced in. diameter at its lower portion 16a.

An annular ring indicator 17 is adhered or otherwise attached to theexternal surfaceof the outer plunger 15 near its lower end, but aboveits lower tapered surface 15a. Such ring indicator 17 may be made ofblack rubber or similar material so that it is visible when adjacent thegraduations or volume indicia on the external surface of the body 10adjacent the upper bore 11 as best seen in FIG. 1.

The taper or inclination of the lower surface 15a corresponds closely tothe taper or inclination of the seating surface 14 within the body 10.Preferably, the angle of the tapered surface 15a extending upwardly andoutwardly is slightly greater than the angle of inclination of thesurface 14 for more effective sealing contact when the surfaces 15a and14 are brought into engagement.

A removable nut 18 having internal threads 18a is provided at the upperend 15b of the plunger 15, which upper end 15b is also threadedexternally for receiving the internal threads 18a of the nut 18.Ordinarily the threads 18a and 15b are tapered downwardly and outwardlyso 'that as the nut 18 is threaded downwardly on the plunger example of0.020 inch so that item freely move longitudinally within the inner bore12.

The upper portion 22 of the inner plunger 20 is made of brass or asimilar material and it has an increased diameter or width as comparedto the wire 21 to provide for increased strength-during longitudinalmovements of the inner plunger 20. A handle or head 23 is secured to theupperplunger portion 22 by welding, brazing or other suitable method sothat the handle 23 becomes an integral part of the inner plunger '20. Itshould also be noted that the lower wire -or plunger 21 is attached bybrazing, bonding or other-suitable method to the upper plunger portion22 so that such portions 21 and 22 become integral for operatingpurposes. In some instances, it will be understood that the-entire innerplunger '20 may be made of a single metal or other material. Asillustrated in the :;drawings, the upper l'brass rod section 22 has adiameter of inch so that it is of substantial thickness as compared :tothe lower plunger 21. The inner passage or opening 16 of the outerplunger 15 has an opening sufficient for the upper portion 22 of theinner plunger 20. The reduced diameter opening 16a is of a size which isadequate for the passage of the lower plunger wire 21 therethrough.Preferably, the external surface of the wire 21 should have a diameterwhich is substantially the same as the internal diameter of the loweropening 160 for sealing purposes. The diameter of the opening 16 abovethe lower opening 16:: should be close enough to the diameter of .theplunger portion 22 so that when the nut 18 is :rotated and is moveddownwardly with respect to the outer plunger 15, a compression or inwardradial movement .of the material of the outer plunger 15 causesan-effective seal with the plunger portion 22 to prevent the escape ofgas .or other fluids .between the plunger 15 and the plunger section 22,as will be further noted herein.

As illustrated in FIG. 1, the lower bore 12 is graduated or calibratedfor microliters, while the upper bore 11 is graduated or calibrated for1 milliliter. It will be understood that the volumes in each of thebores 11 and 12 may be varied by changing the dimensions thereofproportionately. For example, the lower bore 12 may be graduated for 1microliter, 10 microliters, 20 microliters, 50 microliters or anysimilar relatively small quantities. The upper bore 11 may begraduatedand calibrated for 1 milliliter, 2milliliters, or even more.

Because of the construction of the syringe of this invention, withthetwo volume sections, it has great versatility and many uses.

.By way of example, the lower bore 12 may be utilized by itself in someinstances for obtaining predetermined sample quantities of liquid. Thus,the needle 25 is injected into the container .having the liquid to besampled or tested, with the plunger at its lowermost position. The lowerplunger wire 21may be in its lowermost position where it may be drawnupwardly so that its lower end is withdrawn into the opening 16a. Then,the outer plunger 15 and the innerplunger are moved upwardly togetherrelative to the body 10 to draw the liquid into the inner lower bore 12until an adequate amount of liquid has been drawn in so as to fill thelower bore 12 and also a portion of the upper bore 11. The outer plunger15 together with the inner plunger 20 may be moved back and forth topurge the inner bore 12 and also the upper bore 11 of air or other gaswhen filling the tube or body 10 with a liquid.

In any event, any air or gas which is present in the syringe .isdischarged by forcing :the .plungers 15 and .20

downwardly so as to leave the lower bore 12 completely filled with thefluid. After the outer plunger 15 and the inner plunger 20 are forceddownwardly together to cause the tapered surface 15a to engage thesurface 14, the inner plunger 20 is moved downwardly relative to theouter plunger 15 until the lower end 21a'of the lower plunger wire 21 isat the uppermost mark having the indicia 16 for 10 microliters inFIG. 1. If 10 microliters are to be discharged or dispensed, the innerplunger 20 is then forced downwardly so that the lower end 21a movesfrom the indicia 10 down to the indicia 0 within the lower bore 12. If alesser amount of the fluid is to be measured out, such as sevenmicroliters, the measured discharge may start at the time the lower wire21a is at the indicia 7 for 7 microliters and then the discharge maycontinue until the lower end 21a reaches the 0 indicia mark. Any otherpredetermined quantities may of course be discharged with the lower wire21 as will be understood.

In some instances, it is desirable to mix and/or blend two or moreliquids in predetermined quantities withinthe body 10 of the syringe S.For example, for dilution purposes, one fluid may be drawn into thesyringe by pulling the outer plunger 15 and in the inner plunger 20together upwardly from the lowermost position of the outer plunger 15 soas to draw the fluid into the lower bore 12. A suflicient amount offluid may be drawn into the bores 11 and 12 to partially fill the upperbore 11, and then the outer plunger 15 together with the inner plunger20 may be forced downwardly to force any gas or air out of the bores 11and 12, leaving only the liquid. The outer plunger 15 may then be seatedwith the lower tapered surface 15a in contact with the tapered surface14, and the lower end of the wire 21a may be moved downwardly until itis aligned with the uppermost mark indicated by the indicia 10 inFIG. 1. The user then knows that he has a measured quantity of 10mircoliters within the lower bore 12. Thereafter, the outer plunger 15,together with the inner plunger 20, are pulled upwardly to draw into thebores 11 and 12 a diluent or other liquid to be mixed with the firstliquid already in the bore 12. The quantity of liquid which is drawninto the bores 11 and 12 is indicated bythe graduation marks on theexternal surface of the bore 10 in proximity to the upper bore 11, whichas shown in FIG. 1 runs from 0 to IML (one milliliter). The two liquidsare actually mixed together by the drawing of the second liquid into thesyringe and the mixture is in a known proportion due to the knownamounts of the liquids which have been drawn into the syringe body 10.Therefore, such liquids are thereby mixed and blended and may bedischarged as a mixed or diluted fluid. The indicia band 17 becomesaligned with the various graduation or calibration marks on the upperbore 11 in the preferred form of the invention.

In some instances, it is desirable to use the syringe S for gas samples.It is important in such cases to prevent any escape of gas through thelongitudinal opening 16. Normally, the sealing contact between the wallof the opening 16a and the wire 21 is suflicient to prevent liquid frompassing therebetween, but gases may escapetherebetween in some cases.Therefore, the nut 18 is tightened or rotated so as to move downwardlyon the outer plunger 15 to form a seal with the upper portion 22 of theinner plunger 20. Such seal is effective to prevent the passage of gasesbetween the internal wall of the longitudinal passage 16 and theexternal surface of the nod 22. It will be understood that the gases maybe mixed and/ or blended in the same manner as heretofore described inconnection with the liquids, although a purging of gas or air within thesyringe prior to the introduction of the gas being tested or sampled isessential for accurate results. Therefore, a reciprocation of theplungers 15 and 20 within the body 10 while the needle 25 is within thegas to be sampled is important. For example, the needle 25 may beinjected into a balloon having the gas to be sampled and the gas may bedrawn into the syringe S in a quantity greater than intended to bedischarged for the sample. Then the needle 25 may be withdrawn and theplungers 1S and 20 may be forced to their lowermost positions,evacuating all except a small amount of the gas which might remain atthe lower end of the bore 12. This process can be repeated until it isabsolutely certain that the only possible gas within the syringe is thegas to be sampled. Then the sample of the gas is obtained by againinserting the needle 25 into the balloon or other source of the gas andthe amount of the sample to be used is drawn into the syringe. All ofthe gas, except that which is to be dispensed in the measured quantity,is discharged from the bores of the syringe body 19. A second sample ofanother gas may be then drawn into the bores of the syringe S and mixedor blended in predetermined quantities to get a desired dilution orother blending.

It will be understood that the invention disclosed herein has greatversatility and many uses, and the foregoing uses are merelyillustrative. Since the wire 21 is a standard wire and the bore 12 ismade by the precision shrinking process heretofore described, withoutthe necessity for grinding, the syringe bodies and the plungers and maybe standardized and interchangeable, which is not the case if precisiongrinding is required in the bore 12. Also, it will be understood thatwhen the tapered surface 15a seats upon the surface 14, a seal isobtained between the external surface of the plunger 15 and the internalsurface of the bore 11 to prevent any fluid from flowing around theplunger 15. The tapered surface 15a also tends to force the inner wallof the opening 16a into tight sealing engagement with the wire 21 toprevent any escape of fluid upwardly along the rod 21 through theopening 16a. When the seal has been established, the wire 21 then movesdown and as it moves downwardly from the lower end of the plunger 15, itdisplaces fluid in accordance with the cross-sectional area of the wire21 and the stroke of such wire. Therefore, even though there is a spacebetween the wire 21 and the internal bore 12, a predetermined quantityof fluid is discharged by the wire 21 and such predetermined quantity isin accordance with the calibrations on the side of the body 10 adjacentthe bore 12 as illustrated in FIG. 1.

Also, when taking gas samples, it is desirable to provide a gas-tightseal around the rod 22 by tightening the nut 18, as previouslyexplained, so that the gas is prevented from escaping between the innerrod 22 and the wall of the passage 16 in the outer plunger 15.

Various other modifications and changes will occur to those skilled inthe art. It is understood that the particular materials disclosed hereinare merely by way of example and ar not intended to be limiting.

The foregoing disclosure and description of the invention isillustrative and explanatory thereof and various changes in the size,shape and materials, as well as in the details of the illustratedconstruction, may be made within the scope of the appended claimswithout departing from the spirit of the invention.

What is claimed is:

1. A syringe, comprising:

(a) a transparent tubular body having a lower bore and an upper bore,

(b) said body having volume marks for indicating variou volumes withineach of said bores,

(c) said upper bore having a larger diameter than said lower bore,

((1) an outer plunger disposed in said upper bore for longitudinalmovement therein,

(e) said outer plunger is visible through the wall of said upper bore,

(f) said outer plunger having a longitudinal opening therethrough,

(g) an inner plunger extending through said longitudi nal opening ofsaid outer plunger and movable longitudinally thereto and into saidlower bore for discharging a predetermined quantity of fluid from saidlower bore, and

(h) said inner plunger being visible through the wall of said lowerbore.

2. A syringe, comprising:

(a) a glass body having a lower bore and an upper bore,

(b) said upper bore having a larger diameter than said lower bore,

('0) a polytetrafluoroethylene outer plunger disposed in said upper borefor longitudinal movement therein,

(d) said outer plunger having a longitudinal opening therethrough, and

(e) a metal inner plunger extending through said longitudinal opening ofsaid outer plunger and movable longitudinally relative thereto and intosaid lower bore for discharging a predetermined quantity of fluid fromsaid lower bore.

3. A syringe, comprising:

(a) a tubular body having a lower bore and an upper bore,

(b) said upper bore having a larger diameter than said lower bore,

(c) an outer plunger disposed in said upper bore for longitudinalmovement therein,

(d) said outer plunger having a longitudinal opening therethrough,

(e) said outer plunger having a sealing section,

(f) said tubular body having a seating surface between said upper boreand said lower bore adapted to be engaged by said sealing section forsealing off said lower bore from said upper bore,

(g) an inner plunger extending through said longitudL nal opening ofsaid outer plunger and movable longitu-dinally relative thereto and intosaid lower bore for discharging a predetermined quantity of fluid fromsaid lower bore, and

(h) said inner plunger having a diameter enough smaller than the lowerbore to avoid forming a seal therebetween, whereby the volume of fluiddischarged by said inner plunger is a product of the cross-sectionalarea and the longitudinal stroke of said inner plunger.

4. A syringe, comprising:

(a1)J a tubular body having a lower bore and an upper ore,

(b) said upper bore having a larger diameter than said lower bore,

(c) an outer plunger disposed in said upper bore for longitudinalmovement therein,

(d) said outer plunger having a longitudinal opening therethrough,

(e) siaid outer plunger having a lower external tapered (f) said tubularbody having an annular inclined surface between said upper bore and saidlower bore adapted to be engaged by said tapered end of said outerplunger for forming a fluid-tight seal therewith, and

(g) an inner plunger extending through said longitudinal opening of saidouter plunger and movable longitudinally relative thereto and into saidlower bore for discharging a predetermined quantity of fluid from saidlower bore,

(h) said outer plunger sealing around said inner plunger to provide afluid-tight seal therebetween.

5. A syringe, comprising:

(a?) a tubular body having a lower bore and an upper ore,

(b) said upper bore having a larger diameter than said lower bore,

(c) an outer plunger disposed in said upper bore for longitudinalmovement therein,

(d) said outer plunger having a longitudinal opening therethrough,

(e) an inner plunger comprising an upper pusher rod connected to a lowerplunger wire, said wire extending through the lower end of said outerplunger and into said lower bore for discharging fluid from said lowerbore, and

(f) said upper pusher rod providing increased strength as compared tosaid wire to prevent breakage or bending of the lower plunger wire inuse.

6. A syringe, comprising:

(a) atubular body having :a lower bore and an upper bore,

(b) said upper bore having, a larger diameter than said lower bore,

(c) an outer plunger disposed in said upper bore for longitudinalmovement therein,

((1) said outer plunger having a longitudinal opening therethrough,

(e) an inner plunger extending through said longitudinal opening of saidouter plunger and movable longitudinally relative thereto and into saidlower bore for discharging a predetermined quantity of fluid from saidlower bore, and

(f) means for compressing the upper end of said outer plunger intosealing engagement with said inner plunger to prevent the escape of gasor other fluid through said longitudinal opening in said outer plunger.

7. AsyIing'e, comprising:

(a) a tubular body having a lower bore and an upper bore,

(b) said upper bore having a larger diameter than said lower bore,

(c) an outer plunger disposed in said upper bore for longitudinalmovement therein,

((1) ,said outer plunger having a longitudinal opening therethrough,

(e) an inner plunger extending through said longitudinal opening of saidouter plunger and movable longitudinally relative thereto and into saidlower bore for discharging a predetermined quantity of fluid from saidlower bore,

(f) the upper end of said outer plunger being formed of a compressiblematerial and having external threads formed thereon, and

(g) a nut threaded on said external threads for slightly compressing theupper end of said outer plunger to form a fluid-tight seal with saidinner plunger to prevent the escape of gas or other fluid through saidlongitudinal opening in said outer plunger.

References Cited by the Examiner UNITED STATES PATENTS 1,612,996 1/27Waagbo 222-386 X 1,693,261 11/28 Sweetland.

2,841,145 7/58 Epps.

3,140,078 7/64 Krahe et al 222--386 X 3,153,496 10/64 Johnson 222--386LOUIS J. DEMBO, Primary Examiner.

CHARLES R. CARTER, Examiner.

1. A SYRINGE, COMPRISING: (A) A TRANSPARENT TUBULAR BODY HAVING A LOWERBORE AND AN UPPER BORE, (B) SAID BODY HAVING VOLUME MARKS FOR INDICATINGVARIOUS VOLUMES WITHIN EACH OF SAID BORES, (C) SAID UPPER BORE HAVING ALARGER DIAMETER THAN SAID LOWER BORE, (D) AN OUTER PLUNGER DISPOSED INSAID UPPER BORE FOR LONGITUDINAL MOVEMENT THEREIN, (E) SAID OUTERPLUNGER IS VISIBLE THROUGH THE WALL OF SAID UPPER BORE, (F) SAID OUTERPLUNGER HAVING A LONGITUDINAL OPENING THERETHROUGH, (G) AN INNER PLUNGEREXTENDING THROUGH SAID LONGITUDINAL OPENING OF SAID OUTER PLUNGER ANDMOVABLE LONGITUDINALLY THERETO AND INTO SAID LOWER BORE FOR DISCHARGINGA PREDETERMINED QUANTITY OF FLUID FROM SAID LOWER BORE, AND (H) SAIDINNER PLUNGER BEING VISIBLE THROUGH THE WALL OF SAID LOWER BORE.